Andreas Johansson (andreasj@gmail.com) wrote:
<Only, monoplane flyers were old news by 125 Mya. If the four-winged
configuration is older, Micro was a late straggler.>
*Microraptor* may represent the descent of a four-winged model (including
*Pedopenna* and possibily similar animals to *Archaeopteryx*) prior to the
*Archaeopteryx/birds group developed. Thus, ancestrally, the four-winged model
may have enabled the two-winged model, at least as it comes to birds. This may
be contested, as there is evidence to suggest that two wings preceded four, and
that cursoriality (and incline running) lead to the formation of aerofoils and
wings, and arboreality. Thus, while some other views of Chatterjee's are
unorthodox and particular to him, the view espoused in the article is very
plausible and currently at favor with the evidence. It just needs more support
to outweight other possibilities, largely those favored by phylogenetic
analysis.
Cheers,
Jaime A. Headden
http://bitestuff.blogspot.com/
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
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